ABSTRACT

Photoproducts and the yellowing of coatings There are many reasons that a cured coating may display some yellowing. There may be intrinsic color shown from some of the additives, such as thioxanthone photoinitiators, and the formation of yellow photoproducts may occur from the decomposition or rearrangement of the radical species. Tertiary amines tend to bring long-term yellowing1 due to atmospheric oxidative processes, particularly with outdoor applications.